This invention relates to an industrial weigh scale that determines the weight of an object when the object is placed on a weighing platform, and in particular to a weighing apparatus that determines total weight on the apparatus by using a plurality of load-indicating transducers for rapid weight determination.
U.S. Pat. No. 4,066,140 is representative of the prior art that has addressed apparatus associated with heavy-duty industrial scales. This patent describes load-indicating transducers mounted adjacent each of the four corners of a rectangular weighing platform constructed of spaced apart and parallel I-beams. As this patent points out in its BACKGROUND statement, "a major portion of the expense of an industrial scale is directly related to the height of the scales". Even though the '140 patent addressed this height problem, the invention described did not solve this problem, because adjacent each corner of the weighing platform, a complete load-indicating transducer assembly is located on a base underneath an associated I-beam.
U.S. Pat. No. 4,549,622 attempts to solve this problem by placing some of the load-indicating transducer components up within a weakened beam that has been notched. This solution will work for relatively light loads, but leaves a considerable uncertainty as to when the weighing platform will break as the loads get heavier. Notching a beam forms a weak point that will undoubtedly break before the rest of the beam if the load gets heavy enough.
Another patent, U.S. Pat. No. 4,828,055, attempted to solve the height problem by placing the load-indicating transducers between individual, pivotally supported, sections making up a complete weighing platform. This patent suffers from a construction problem in that the load measuring apparatus is positioned between the pivotally supported sections. This apparatus is not adapted to be used with conventional I-beams, which do not pivot, although these I-beams are generally used in a conventional weighing platform. Conventional I-beams have a very definite advantage in constructing a weighing platform because they are readily available and are in widespread use.
From the above, it can be seen that what is needed is a heavy duty weigh scale that can be constructed with conventional I-beams and still have a compact height from ground to the top of the weighing platform.